Uninstallation shows successful even when not installed

[markmcnaughton]

Describe the bug

When uninstalling a package version that is not installed, tenv reports the operation as successful even though the version is not installed and/or does not exist.

e.g.
❯ tenv tf uninstall 0.0.0
Uninstallation of Terraform 0.0.0 successful (directory /home/USERNAME/.tenv/Terraform/0.0.0 removed)

❯ tenv tofu uninstall 0.0.0
Uninstallation of OpenTofu 0.0.0 successful (directory /home/USERNAME/.tenv/OpenTofu/0.0.0 removed)

❯ tenv tg uninstall 0.0.0
Uninstallation of Terragrunt 0.0.0 successful (directory /home/USERNAME/.tenv/Terragrunt/0.0.0 removed)

To Reproduce
Steps to reproduce the behavior:

1. List the available or installed versions:

tenv tf list-remote

tenv tofu list-remote

tenv tg list-remote

2. Verify that version 0.0.0 is not installed.

3. Attempt to uninstall the non-existent version:

tenv tf uninstall 0.0.0

tenv tofu uninstall 0.0.0

tenv tg uninstall 0.0.0

4. Observe that the command reports a successful uninstallation, for example:

Uninstallation of Terraform 0.0.0 successful (directory /home/USERNAME/.tenv/Terraform/0.0.0 removed)

Expected behavior

If the requested version is not installed, the command should return an error or warning instead of reporting success.

For example:

Terraform 0.0.0 is not installed.

or

Uninstallation of Terraform 0.0.0 failed: version is not installed.

Screenshots
N/A

Environment (please complete the following information):

OS: Arch Linux - 7.0.10-arch1-1
tenv version: v4.14.8

Additional context

The current behavior appears to treat the removal of a non-existent directory as a successful uninstall. It may be worth checking whether the target version exists before reporting success.

[suman2280]

I'd like to work on this if no one else is already doing so.